The Methane Cycle

Comments

Good evening Robin Grieve,
I would like to draw your attention to your methane cycle cartoon and point out that it is incorrect.

What you have shown is merely the portion of the methane cycle that the atmospheric scientists like to believe. According to them, the oxidation of methane back to CO2 occurs high in the atmosphere where incoming high-energy photons are available to “crack” the relatively inert CH4 molecule.

Unfortunately, like the vast majority of the greenhouse gas/climate change proponents, the atmospheric scientists lack the breadth of education to know the full extent of the methane cycle. They fail to know that, like all biologically cycled chemicals, the real controllers of the cycle are microorganisms.

In the case of methane, this molecule is largely controlled by a group of bacteria known as methanotrophs. There are quite a few varities, many are aquatic, but some are terrestrial and live in the soil of farms and forests. They take methane (and sometimes other 1-carbon molecules such as methanol) and “break” it using a protein enzyme that appears to have evolved from the protein used by nitrogen fixing bacteria to “crack” one of the 3 bonds holding the very stable atmospheric N2 molecule together. In fact some of the nitrogen cycle bacteria appear to be able to also “crack” methane. In other words there is a lot of methane removal happening on the farm.

Some of the methane metabolised is used for energy and the carbon is released as CO2. The rest is used as a carbon source for building cell components.

You may be aware that in the natural world the greatest producer of methane is swamps, bogs, estuaries, rice paddies and other such wetlands (per square metre). This is net methane after the methanotrophs in the oxygenated top layers of water have taken their needs. I will point out that this net output is considerablely higher than the gross output (per square metre) as measured by livestock respiration logging. This is BEORE accounting for methane uptake by the bacteria living in the soil that the animal is standing on. Which of course the agricultural scientists have not (so far) measured.

I have yet to hear of the Greenies demaning carbon payments from builders of new or restored wetlands for their methane contribution. But I have pointed out to the Ministry for the Environment that if farmers are to be taxed for livestock then so should wetland builders.

The metabolism of the methanotrophs appears to be inhibited by high levels of nitrogen fertilizers, so I suspect that the use of nitrogen inhibitors to reduce nitrous oxide emissions in fact reduces methane uptake resulting in higher methane emissions from treated farmland.

On the other hand, organic fertilizer use has been shown to produce a 3x greater activity by methanotrophs so organic farmers may be due some credits.

Forest soils are also known to be good methane sinks due to their relatively higher oxygenated nature. (Unfortunately this also enhances decomposition bacteria activity which causes forest soils to tend towards losing their organic matter and emitting it as CO2 to the atmosphere – one of several GHGs released by trees – scentists in the field of tree/atmospheric interaction explicity declare that it is so complex it is not, so far, possible to determine whether trees contribute to global warming or help prevent it. Funny how the Greenies and the Government choose to only know that trees suck up a bit of CO2 but don’t (want to) know the full story).

My personal muse is to consider what would happen if we suddenly were able to prevent methane emissions from livestock. I have to suspect that many of the populations of methanotrophs in the soil would be threatened by this loss of food supply. (Loss of biodiversity – isn’t that a Greenie no-no). At the very least they would shut down their metabolism and the rest of nature would carry on pumping out methane until sufficient levels were restored to switch the bacteria on again – i.e. taking away the livestock production would not change atmospheric levels in the long run. In fact if sufficient bacteria were killed, the levels of methane could overshoot the current concentration, while we await repopulation of the soils.

Which brings me to the atmospheric levels of methane. I have not seen you mention this so I will assume you do not know it, or can not put it in to context.
The Greenies blow hard about methane emissions giving the impression that like CO2 the levels are rising dangerously. Actually the methane concentration is about 1.7 to 1.8 parts per million, on average, and has been steady for a number of years.

When the Kyoto protocol was put together, global levels were rising. This was due to fossil fuel industry releases. Methane used to be an almost junk fuel, worth very little. In fact the British tried to develop food production by feeding their “waste” gas from the North Sea oil fields to methanotrophs contained in vats and Norway still does this to produce fish food for salmon farms. Methane excesses were often dumped into the air. When fuel prices increased methane became valuable so it was kept and in particular the Russians started to patch their leaky network pipes and methane rises started to quickly level off.

There has been a reported rise last year – I am sure this will be also traced to the fossil fuel industry thanks to the boom before the bust.

Ok so what does 1.8 ppm of methane mean. Firstly when Greenies say methane is a powerful GHG this is in order to distract attention from the fact that there is practically none in the atmosphere. (by the way it isn’t a powerful GHG anyway – there are aluminium smelter GHGs that have a CO2 equivalence of 23,000, now thats powerful!). Imagine a kilometre of atmosphere over your head – 1000m at 1000mm per metre is 1 million millimetres of air. Separate the various component gases into layers and methane does not even fill the first 2 millimetres. Compare that to an average of 10 metres of water vapour (also a GHG), and you can see that methane is not the tail wagging the climate change dog- it would have to be the virus on the bacteria on the tail of the dog.

Now multiply 1.8ppm by a generous 25, to give a CO2 equivalent forcing, equals 45ppm of CO2. If you have seen the Hawaii historical atmospheric record of CO2, you will note the zigzag nature of the inceasing general curve. The zigzag is caused by the Northern Hemisphere forests. As they drop leaves in their autumn, these decay releasing CO2. In the spring they suck up CO2 to make new leaf growth. The magnitude of yearly change in one source I have is about 20ppm, other sources calibrate the change to about 12-15ppm.

Bottom line – the effect of methane on the globe is about equivalent to 3 times the Northern Hemisphere’s collection of tree leaves (non-evergreens of course). Wow, really powerful – not. And the amount of woodland across those countries is considerable less than what used to be there before farming was invented.

By the way, coal mining methane emissions are only accountable under Kyoto rules when they are released from the coal face during the actual mining. Most underground mines are now degassed for safety and/or fuel use before mining occurs. This release and the release of methane, CO2 and CO from the surface of coal layers exposed by overburden removal during opencast mining is not accountable and according to a letter writer last year to the New Scientist magazine, can amount to twice the amount of carbon released from using the actual coal. Also in opencast mining a considerable amount of coal is discarded because the ash content is too high for power station use. This coal eventually also oxidises and the carbon released to the atmosphere. This is one of the factors that makes NZ’s so called carbon footprint appear large compared to other countries – most countries are dependent on coal for power and don’t have to report their real emissions!

All this methane going into the atmosphere from wetlands, termites (the biggest animal source), rice paddies (the biggest man-made source), coal mining and other fossil fuel leaks and yet atmospheric levels are steady, more or less. The amount of removal by atmospheric chemistry is, I presume, a constant since the suns output of photons is more or less constant, so I presume that forest and farmland uptake is balancing out all the above methane releases.

In other words: the Greenies want to tax farms for methane releases that they probably don’t make, and are carbon neutral if they do, they don’t want to tax wetlands but farms and forests have to help clean up those emissions, they don’t bother with the huge methane releases from coal mining dispite that these are carbon increases and farms and forests again have to help reduce the effects of these emissions by converting them to CO2.

And finally the Greenies want to tax farms that possibly are actually negative net emitters, in order to pressure farmers to reduce livestock emissions, yet livestock do not contribute to increased levels of carbon or methane and removal of their emissions is unlikely to change atmospheric concentrations of methane.

Thanks Michael, I am hopeful that one day soon real science will prevail and it is those with the knowledge, such as yourself, that we need to call to account the spurious claims of the climate scientists and their political latch ons.

Everything you say is consistent with our belief that certain sectors are being blamed for emissions that don’t exist such as agriculture and other sectors are being let off emissions that do exist such as forestry, and wetlands etc.

A very interesting site Robin. You need to get this stuff out into the mainstream media so that everybody knows what is going on. I am amazed that Federated farmers are not up in arms over the Govt trying to rort farmers in this way. I thought National and Act were going to get rid of all this when I voted for them but they are just as bad as the last lot.
cheers, Bruce

I actually had to show this specific article, “The Methane Cycle | Pastural Farming Climate Research” along with my best close friends on facebook itself.
I personallyjust wished to disperse ur remarkable writing!
Thanks a lot, Denisha